Super Secret Hypersonic Aircraft Flew Out of Its Skin | Hacker News Reader

Super Secret Hypersonic Aircraft Flew Out of Its Skin

darpa.mil

56 pointsdevy21 comments

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I'm not sure if it can still be described as 'super secret' if we're reading about it on the official DARPA blog.

The latest missiles and bombers were always paraded to the foreign press in Red Square.

Seeing, counting and not knowing is fearing.

And at home, its securing funding too, of course.

Indeed, nothing about it being secret appears anywhere in the blog posting, prosaic title is:

ENGINEERING REVIEW BOARD CONCLUDES REVIEW OF HTV-2 SECOND TEST FLIGHT

And it's quite cool; of particular note is their analysis that the improvements prompted by the previous first test allowed the flight control system to keep it stable for a while as the skin was peeling off and creating nasty aerodynamic effects. And I gather they have some real world to provide the materials science types.

According to this Yahoo! News article: http://news.yahoo.com/super-secret-hypersonic-aircraft-flew-...

"While the test was very public, the details of the HTV-2's design, stability system and potential purpose remain highly classified."

For those interested, at mach 20 it seems to take 98 minutes to go around the equator (on the surface). In the nine minutes of sustained flight, it could have covered 3675km on the ground.

Like a banana through a fence.

Seriously if you've never done it - throw a banana HARD through a fence. Quite interesting.

Yes I am insane.

Skinned? Chain-link?

I... would like to see a video of this.

http://www.youtube.com/watch?v=bVa15C0xHSo

I love the Internets.

It really sounds like the only real problem was the material that covers the aircraft not being able to withstand the forces at mach 20. I wonder what the material was and if they can find something better without a lot more materials research. I love this stuff!

So given this thing goes Mach 20, how fast does it get there?

If the intention is to have a platform that can deliver 'stuff' (whether munitions, supplies or people) is there going to be a problem with g-loading on acceleration and deceleration?

Are they going to continue this research or was that the last flight?

It was my understanding from previous articles that this is an ongoing project.

They should take an Fail Fast approach, why not make several test flights at 10000 and look for problems. 400 Million for the first flight seems really expensive.

They have a fair amount of experience going about it the way they do (since the X-1). It looks like it will take a while to go through all the data and figure out what material / structure changes they need to make. It also makes a couple of other countries a little antsy flying this type of beast.

it did a barrel roll at 13,000 miles per hour... and corrected itself

It was probably a roll, not a barrel roll since the latter requires a controlled pitch input.

What is secret about something written about publicly?

Do you know how to build it? Me neither.

Wait a second -- neither do I! So if the two of you not knowing how to build it means it's secret (your point, right?)...then the three of us not knowing means it's... TOP SECRET!

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